Nestable egg trays



NOV. 1, G A RUDD NESTABLE EGG TRAYS Filed Dec. ll, 1964 :3 Sheets-Sheetl INVENTOR G. A. RUDD Nov. 1, 1966 NESTABLE EGG TRAYS 5 Sheets-Shee 2Filed Dec. ll, 1964 INVENTOR Km2. (L). `FLoc; rg

ATTORNEY G. A. RUDD Nov. 1, 1966 NESTABLE EGG TRAYS 5 Shees-Sheet 5Filed Deo. ll, 1964 IDR/Of? ART INVENTOR ATTORNEY United States Patent O3,282,458 NESTABLE EGG 'I'RAYS Gerald Arthur Rudd, Corton, nearLowestoft, Sulolk,

England, assigner to Diamond International Corporation, New York, N.Y.,a corporation of Delaware Filed Dec. 11, 1964, Ser. No. 417,651 Claimspriority, application Great Britain, Dec. 24, 1963, 50,934/ 63 4 Claims.(Cl. 217-265) This invention relates generally to packages used instoring, handling, and shipping eggs and like ovate articles, and ismore particularly related to improvements in nestable trays whichinclude means `for not only protecting the articles being packed lbutalso include means whereby the trays may be readily nested and denestedto facilitate all of the advantages of production-line handling andpacking of packages.

It Ihas heretofore, and still is, the co-mrnon custom to pack eggs forshipment in corrugated cases or wooden crates in which paperboardfillers and flats 'are used, each flat having cells for receiving theindividual eggs and the fillers separating the individual eggs.

Combination filler flats or trays of the character involved in thepresent invention are ygenerally produced from a fiber material, ie.,are mass-'produced on machines carrying suction dies, which are passedduring operation through a suspension or slurry of fibers, whereby thelatter are deposited in the form of a felt on the surface of the die ina layer.

The deposited fibers, which are initially suspended in fluid, generallyprovide for a suitable softness andV resilience, however, the requisitestrength, cell capacity, etc., is achieved through the use of specificstructural components and design of the cells.

The trays or filler ats must be so strong that they can support the eggswhen being lifted at opposite edges, i.e., most conventional traysincluding recesses to form hand grip portions on two opposite sides.

An object of the present invention is to provide a molded tray producedfrom a molded pulp or papiermache which includes means for preventingjamming of the trays when they are nested one within the other forstorage, shipment or denesting from automatic equipment 'and yetpermitting the nested trays to be readily separated without tearing ordestroying portions of the trays.

Another object of the present invention is to provide in a tray of thecharacter mentioned above, a plurality of equi-spaced .support postsarranged in longitudinal and transverse rows extending upwardly `from abas'e p'llane wherein intermediate rows of posts depend from the baseplane and define egg-containing cells or pockets with -the supportposts, and in which adjacent support posts are interconnected byrect-angularly arranged ribs combining to form a partial side wallenclosure `for the cells or pockets and to define each cell in a:general-ly rectangular pattern with a support post at each corner.

A `further object of the present invention is to provide in a tray ofthe character -set forth .above support posts -which may geometricallylbe described as formed by revolving a curved line about `a verticalaxis with the curve being concave on the side away from said axis, thushaving an outer concave wall land which also generally terminates in alateral land and in which the sides of Vthe cells or pockets may IbeIgeometrically described as Patented Nov. .l l 966 ice being formed byrevolving a compound curve of varying radii and having an outer concavewall terminating in said lateral land.

Another object is to provide a tray wherein the inner surface Iof eachcell preferably has an upper portion extending upwardly :and outwardlyso that la tangent to said upper portion is substantially at an angle of20 to the vertical 'axis of said cell and a lower portion eX- tendin'gdownwardly and inwardly so that la tan-gent to said lower portion issubstantially at an angle of 30 to said axis.

Another object is to provide a tray wherein the surface of each celltherein is curved continuously over its whole height or it may haveportions which are straight or substantially straig-ht in verticalsection (e.g., at the top `and bottom of the surface), provided thatsaid portions are merged smoothly in a curve, in vertical section, withthe remainder of the surface. v

Another object is to provide a tray wherein support posts lare `soformed and spaced .as to present a relatively large opening facilitatingsmooth entry of eggs into depending cells and wherein the cells have laconcave int'erior surface of compound curvature to accommodate differentsize elggs and provide a large support area and a convex underside tocircumferentially contact the upper portions of eggs supported in cellsof `a similar tray below the first-mentioned tray, said surface having aconcave interior and a convex underside being generated by revolving acompound curve.

Another object is to provide a tray including depending cells having asubstantially rectangular base configuration and including upwardlyextending support posts having a circular top configuration so that whenthe trays are stacked ione upon another when loading a case or crate the`bottoms of depending cells will engage upper terminal portions of thesupport posts to provide proper transmittal of vertical loadtherethrough.

And yet a still further object of the present invention is to provide ina tray of the character mentioned, articlecontaining cells or pocketsformed by means of =a plurality of spaced stiffening ribs projectingoutwardly from the inner face of the pockets fand upwardly from thebottom of an :associated pocket to approximately midway of the height ofsaid cells or pockets, said ribs being spaced about the circumference ofan associated post and .generally comprising four stifiening ribs eachof which having an outer configuration substantially distinct anddifieren-t from a downwardly opening recessed or associated pockettherebeneath, whereby .the ribs not only strengthen the lassociated postlagainst collapse during `nesting of th'e trays, but also reinforce thepost so asl to provide strength to the trays when they are lifted withthe cells loaded with eggs, -and also provide for increased strength forthe transmittal of vertical 'loads in or through a stack of loadedtrays.

These together with other and more specific objects and Iadvantages ofthe invention will be understood from a consideration of the followingdescription when taken in conjunction with the drawings forming a partthereof, whe-rein:

FIG. l is a plan view of an egg tray embodying the features of theinvention;

FIG. 2 is an end elevation looking inwardly at the lower edge of FIG. l,as indicated by the direction arrow identified as A;

ansa/ree FIG. 3 is a vertical section taken substantially on the planesof line 3 3 of FIG. l;

FIG. 4 is a side elevation taken ysubstantially from right to left atFIG. l as indicated by th'e direction arr-ow Ilabeled B;

FIG. 5 is yan enlarged fragmentary section taken substantially `on theplane of line 5 5 of FIG. 1 and showing more specifically exact detailsand the configuration of one of the tray cells;

FIG. 6 is an enlarged fragmentary section tak'en substantially on theplane of line 6 6 of FIG. l, showing details of *the novel ribconstruction 'and configuration of the support post about which cellsare formed;

FIG. 7 is :an essentially diagrammatic view showing a pair of trays injuxtaposed relation wherein the upper tray has been rotated 90 andjuxtaposed on the lower tray for illustrating the egg-receiving areasformed between the egg-receiving cells of the bottom tray, and thecorresponding egg-receiving portions afforded by the undersurface of theuppermost tray;

FIG. 8 is a diagrammatic view illustrating theoretically how a pluralityof eggs are received in the cooperating egg-receiving portions ofjuxtaposed trays;

FIG. 9 is a fragmentary section showing the nesting of two tray portionsand illustrating the manner in which portions of the egg tray ribs nestand facilitate ready denesting;

FIG. 10 is an enlarged fragmentary view of a portion of FIG. 8 moreclearly illustrating the support surfaces afforded by an egg-receivingspace between la pair of juxtaposed cooperating trays; and

FIG. 1l is a diagrammatic view, similar to FIG. l0, showing thetheoretical supp-ort surfaces afforded by true conical egg-receivingcells and similar cooperating portions of the undersurface of such atray juxtaposed thereon.

Referring to the drawings in detail, it will be understood that the eggtray of this exemplary embodiment is a substantially rectangularorsquare sheet 0f fiber mass which is generally mass-produced onmachines carrying suction dies, which dies are passed during operationthrough a suspension of fibers, whereby the fibers are deposited on thesurface of a die.

The tray to presently be `described in ldetail is that of the typeconventionally 'described as a 5 x 6, i.e., will hold thirty eggs or twoand one-half dozen eggs. Inasmuch as the novel cells and othercooperating portions of the tray are substantially duplicated throughoutthev tray, only one of the cells and posts will be described in detail.

A tray is indicated generally at 10 and comprises a rectangularone-piece body member 12 produced as a single sheet lof fiber mass andhaving a peripheral marginal flange 14 substantially bordering all sidesthereof with the exception of indented or hand grip portions 16 and 18at opposite sides thereof. The peripheral fiange 14 defines a base planefrom which other cooperating portions of the tray will be related andidentified.

The body member 12 includes a plurality of pockets or cells indicatedgenerally at 20 produced in rows extending crossvvise and lengthwise ofthe sheet, equally spaced apart from one another and forming a regularpattern. Between these pockets there `are provided projections indicatedgenerally at 22 which follow a similar pattern. The projections or posts22 are interconnected by horizontally disposed and circumferentiallyspaced ribs 24 disposed at 90 intervals.

Details of the cells, posts and horizontally disposed ribs will besubsequently described, particularly with respect to FIGS. 3-6. In the 5x 6 tray, six posts in a row extend in one direction, and five posts ina row ex` tend normal thereto. Halfposts are provided adjacent thedirection in which the five posts in a row extend, and these half-postsare indicated at 26. Additionally, as indicated at 28, half-cells areformed at opposite ends of the tray in which a row of five cells appear.The halfposts and halfcells will not be described in detail.

Referring to FIGS. 2-6, and particularly considering the ribs 24, itwill be noted that these ribs have generally what might be described asa Wishbone or inverted Y shape and have a substantially rectangular butbulbous top portion 30 which is produced from a build-up of the fibersfrom which the tray is produced. In this relatively confined and narrow'area of the lsuction die, as pulp is initially sucked into this area,fibers will pile up or be of a built-up character, i.e., the fiberspiling upon each other and bridging across. Though the recess in the diefor forming the portion 30 i-s rectangular with parallel sides, owing todifferential shrinkage on drying, the sides 32, 34 become undercut inthe final product as illustrated in FIG. 6. lThus, the portion 30, whenviewed in section as in FIG. 6, has a bulbous top, inwardly taperedsides which continue into a pair of diverging legs 36 and 38 which forma downwardly opening substantially inverted V-shaped nesting groove 40extending the length of the horizontally disposed ribs for overlying thesimilar rib of a tray which is nested below that of the character shownin FIG. 6, for example (see FIG. 9). The tray horizontally disposed rib,which will be nested in the groove 40, will have an upper configurationof the character shown at 30in FIG. 6, and thus jamming or impaction ofnested trays will be prevented. The upper edge of the ribs 24 will bedisposed a distance S from the upper surface of the peripheral flange 14to the upper edge of such ribs, 'and this provides a denesting spacingto prevent the similarly conformed posts and depending cells ofjuxtaposed trays from becoming impacted and difficult to separate. Theribs are solid in cross section, i.e., are undercut from the upper edge,and have a width or cross section substantially greater than the normalthickness ofthe blank.

The legs 36 and 38 extend laterally in foot portions 42 and 44 which areconnected to downwardly diverging wall portions 46 and 48 comprisingportions of the cells 20.

The posts 22 project above the base plane defined by the peripheralflange 14 and comprise ya concave surface generated by an inwardlyextending compound curve revolved about a vertical axis, i.e., the posts22, when viewed in elevation as seen in FIGS. 5, 6 and l0, for example,have a concave outline when viewed in vertical section, as indicated at50. The oute'rside of the posts 22 have been described as having aconcave surface and thus it will be understood that the underside of theposts 22 is substantially in the form of a corresponding surface ofrevolution generated by a convex curve. The interior surface of eachcell has a section which is smoothly curved and concave in verticalsection, as illustrated, for example, in FIGS. 5, 8 and l0. The lowerportions of the inner surface of each cellextends downwardly andinwardly so that a tangent thereto is at an angle of substantially 30 tothe vertical axis of the cell while the upper portion of the innersurface of each cell extends upwardly and outwardly so that a tangentthereto is at an angle of 4substantially 20 to said axis. In this Way,the part of the inner surface of each cell which will be engaged 4by anegg is given the desired general inclination while the required heightof the posts is obtained. The concave inner surface of each cell willengage a larger area of Contact with the convex surface of an egg, thusmore firmly and safely supporting the egg. The steeper upper wallportion of the cell provides greater resistance to collapse undervertical load than if the Whole wall was, like the lower portionthereof, less steeply inclined. The tray in accordance with theinvention can be used for eggs of different sizes and the configurationof the tray is such that the cubic capacity of the egg case or egg traywithin which the loaded trays are stacked is efficiently utilized.

The ycells 20 have circumferentially spaced thereabout verticallyextending flutes 54 which facilitate the production of the cel-ls 20with a substanti-ally rectangular base 56. rIlhis rectangular base, itwill -be observed, has extending from each of the corners thereof one ofthe flute-s 54 which merge into the side of the post 22 and,accordingly, reinforce the same.

The cells 20 are defined at their uppermost portion by a circumferentialflange or land 5S comprising portions of the feet 42 and 44 previouslymentioned with respect to the ribs 24. It will be noted that the legs 36and 38 disposed on opposite sides ofthe downwardly opening -groove 40,converge upwardly from the flange or land 58. Further, the terminal endsof the ribs extend integrally with an intermediate portion of the sidesurfaces of the posts 22.

It will be observed in FIG. 5, for example, that the reverse or innerside of the portions 50 of the post 22 having a concave surface 60, thisportion having a delinite function with respect to the upper portions ofeggs stored in an egg-receiving space R as indicated in FIGS. 8 and 10.

Considering FIG. 7, a tray of the character disclosed lin FIG. l willreceive in the cells thereof eggs, and a second t-ray indicated at 10will be positioned thereon; however, it will be rotated 90, i.e., thehand-receiving portions 16 and 18 will be disposed at 90 with respect toeach other on the respective tray-s, as is conventional. When the traysare so oriented, the rectangular bottom surface of the cell bottom 56will be received on the upper circular end portions of the underlyingposts 22. Since the 'bottoms of the cells are rectan-gular, they have aslightly greater area than the upper end portions of the posts 22, andthus, though the trays may shrink nonuniformly, engagement between theposts will be substantially assured.

Referring to FIG. 8, the egg-receiving spaces R comprise the lowerconcave surface 52 and the undersurface or convex surface 60 of theposts, i.e., the lower surfaces oppo-site the surfaces 50.

A-s illustrated essentially diagram-matically in FIGS. 8 and 1l, eggsare conventionally packed small end down and the lower concave portionof the cells 20 will provide a support surface which is relativelybroad, inasmuch as the concave portion will, in a sense, conform or becomplementary to a corresponding portion of the side surface of theeggs. In a sense, a relatively broad support area C is provided for thelower portions of the eggs. However, the convex upper portion of theeggreceiving portions of a pair of cooperating trays will havesubstantially circumferential, linear or tangential engagement, asindicated at T, i.e., a line extending circumferentially about the upperlarger portion of the eggs due to tangential contact with the convexportions 60 of the cells.

Referring to FIG. l1, there is disclosed a theoretically true frustum ofa cone generated by rotating a right triangle about a spaced verticalaxis, as indicated at F. In other words, when the sides of the cells aresubstantially straight in vertical section, -there will only be twolines of contact L, L with the respective upper and lower portions ofthe egg being contacted in the egg-receiving space R.

Referring to FIG. 9, a lower tray 10 has nested thereon a tray 10 andthe cooperating relationship of the lower -rib 24 with respect to theupper lrib 24' is illustrated. It wil-l be noted that the space 40formed above the legs 36', 38 will receive the llower -rib 24 therein,thus preventing the posts and cells of nested trays from becomingimpacted to .prevent subsequent denesting.

Thus, there has been disclosed an egg packing tray or filler-flat whichin itself has egge cells or pockets afforded by a side wall enclosure ina generally rectangula-r pattern and the side wall enclosure is integralwith and extends from intermediate -surface portions of vertical supportposts. This construction includes the ribs which are relatively solidand generally rectangular, though provided with a bulbous head andundercut sides, in cross section and also includes the depending legs orIside wall portions terminating in lateral feet coinciding with an upperflange defining the upper edge of egg-receiving cells which are disposedsubstantially below a base plane defined by a peripheral ange of thetray. This construction facilitates `the lifting of a tray loaded witheggs by providing integral beams surrounding each of the cells filledwith eggs.

When a shipping case is filled by a plurality of the disclosed egg traysto form egg-receiving spaces of the character described, the lowersquare por-tions of the `cells will have intimate contact with the upperends of the posts of an underlying tray to accordingly providetransmittal of vertical load or forces through the trays to the bottomof the packing case or support surface without imposing -load on theeggs packed between juxtaposed trays. Additionally, due to the innerconcave support surface of the cells and the reverse convex surface ofthe egg-receiving space formed by juxtaposed trays, the eggs aremaintained in the cells in a relatively xed position to preventrattling, etc.

When the trays per se are stored, lshipped or disposed in mechan-icaldenesting apparatus, the rectangularly and horizontally disposed ribssurrounding each of these cells will not only reinforce the traysa-gainst damage, hut will facilitate ready denesting of one tray fromanother.

It will be obvious to those skilled in the art that various change-s maybe made without departing from the scope of the invention and thereforethe invention is not limited t-o what is shown in the drawings anddescribed in the specification but only as indicated in the appendedclaims.

What is claimed is:

1. A molded pulp tray comprising a body member having a generally normalthickness and including a peripheral margin defining a base plane, saidbody member including a plurality of hollow posts extending verticallylfrom said lbase plane and a plurality of hollow cells depending fromsaid l1base plane, said posts 'being alternately disposed in transverserows, said body member including ribs spaced in intervals about saidposts yand connecting certain of said posts to each other, said ribsincluding a linear upper edge disposed in a plane above said base planeand extending continuously lbetween said posts, the improvementcharacterized in that said ribs have an upper vbulbous solid portion oflarger cross section than, and converging downw-ardly into, the portionof the ribs therebeneath and substantially thicker than the normalthickness of said body member and integrally formed with pairs of legsof normal thickness disposed below said Ibase plane and diverging in adownwardly opening groove disposed below said base plane and extendingthe length of said ribs and having a concave cross section distinct fromsaid solid =bulbous rib portions and extending upwardly into the base ofsaid ri-bs for preventing impaction of nested trays and permitting readydenesting therebetween, said legs terminating in lateral foot portionsdisposed in a plane below said base plane, said foot portions beingconnected to downwardly diverging side wall portions of said cellswhereby when at least a pair of trays are nested only the juxtaposedupper edge portion of the ribs of the lowermost tray is engaged withside wall -portions of the grooves of the uppermost tray.

2. A tray according to claim 1 characterized in that the outer surfaceof said hollow posts and the inner surfaces of said pocket formationseffectively provide the upstanding vertical posts and hollow cells andinclude a shape corresponding to a surface generated by revolving acompound curve about the vertical axis of said cells and are uniformlyconcave from the top of said posts to the Ibase of said cells wit-hrespect to the vertical axis of these cells.

3. A tray according to claim 2 characterized in that a line tangent tothe upper portion of said posts is substantially 20 with respect to theVertical axis. of the posts and a line tangent to the walls of the cellsAis at substan- 11/1916 Eaid 217-265 r 5/1937- Dorf .217 26.5 L

8 ,Beck 217-265 Putnam 217-265 Millett 229-25 Grant 217-265 Emery217-265 Martelli et al. 229-25 Boyd 217-265 Whiteford 229-25 Hartmann etal. 229-25 Reifers et al. 217-265 THERON E. CONDON, Primary Examiner.RAPHAEL H; SCHWARTZ, Examiner.

1. A MOLDED PULP TRAY COMPRISING A BODY MEMBER HAVING A GENERALLY NORMALTHICKNESS AND INCLUDING A PERIPHERAL MARGIN DEFINING A BASE PLANE, SAIDBODY MEMBER INCLUDING A PLURALITY OF HOLLOW POSTS EXTENDING VERTICALLYFROM SAID BASE PLANE AND A PLURALITY OF HOLLOW CELLS DEPENDING FROM SAIDBASE PLANE, SAID POSTS BEING ALTERNATELY DISPOSED IN TRANSVERSE ROWS,SAID BODY MEMBER INCLUDING RIBS SPACED IN 90* INTERVALS ABOUT SAID POSTSAND CONNECTING CERTAIN OF SAID POSTS TO EACH OTHER, SAID RIBS INCLUDINGA LINEAR UPPER EDGE DISPODED IN A PLANE ABOVE SAID BASE PLANE ANDEXTENDING CONTINOUSLY BETWEEN SAID POSTS, THE IMPROVEMENT CHARACTERIZEDIN THAT SAID RIBS HAVING AN UPPER BULBOUS SOLID PORTION OF LARGER CROSSSECTION THAN, AND CONVERGING DOWNWARDLY INTO, THE PORTION OF THE RIBSTHEREBENEATH AND SUBSTANTIALLY THICKER THAN THE NORMAL THICKNESS OF SAIDBODY MEMBER AND INTEGRALLY FORMED WITH PAIRS OF LEGS OF NORMAL THICKNESSDISPOSED BELOW SAID BASE PLANE AND DIVERGING IN A DOWNWARDLY OPENINGGROOVE DISPOSED BELOW SAID BASE PLANE AND EXTENDNG THE LENGTH OF SAIDRIBS AND HAVING A CONCAVE CROSS SECTION DISTINCT FROM SAID SOLID BULBOUSRIB PORTIONS AND EXTENDING UPWARDLY INTO THE BASE OF SAID RIBS FORPREVENTING IMPACTION OF NESTED TRAYS AND PERMITTING READY DENESTINGTHEREBETWEEN, SAID LEGS TERMINATING IN LATERAL FOOT PORTIONS DISPOSED INA PLANE BELOW SAID BASE PLANE, SAID FOOT PORTION BEING CONNECTED TODOWNWARDLY DIVERGING SIDE WALL PORTIONS OF SAID CELLS WHEREBY WHEN ATLEAST A PAIR OF TRAYS ARE NESTED ONLY THE JUXTAPOSED UPPER EDGE PORTIONOF THE RIBS OF THE LOWERMOST TRAY IS ENGAGED WITH SIDE WALL PORTIONS OFTHE GROOVES OF THE UPPERMOST TRAY.